The pattern of lymph node involvement in carcinoma of the head of the pancreas. A histologic study of the surgical findings in patients undergoing extensive nodal dissections

Overall Survival in Patients with Stage IV Pan-NET Eligible for Liver Transplantation

BACKGROUND

The use of liver transplantation (LT) in patients with stage IV neuroendocrine pancreatic tumors (pan-NET) is under debate. Previous studies report a 5-year survival of 27-53% after LT in pan-NET and up to 92.7% in patients with mixed NETs. This study aimed to determine survival rates of patients with stage IV pan-NET meeting criteria for LT while only subjected to multimodal treatment.

METHODS

Medical records of patients with pan-NET diagnosed from 2000 to 2021 at a tertiary referral center were evaluated for eligibility. Patients without liver metastases, who did not undergo primary tumor surgery, age > 75 years and with grade 3 tumors were excluded. The patients were divided into groups; all included patients, patients meeting the Milan, the United Network for Organ Sharing (UNOS) or the European Neuroendocrine Tumor Society (ENETS) criteria for LT. Kaplan-Meier survival analysis was used to calculate overall survival.

RESULTS

Out of 519 patients with pan-NET, 41 patients were included. Mean follow-up time was 5.4 years. Overall survival was 9.3 years (95% Cl 6.8-11.7), and 5-year survival was 64.7% (95% CI 48.2-81.2). Patients meeting the Milan, ENETS and UNOS criteria for LT had a 5-year survival of 64.9% (95% CI 32.2-97.6), 85.7% (95% CI 59.8-100.0) and 55.4% (95% CI 26.0-84.8), respectively.

CONCLUSIONS

In patients with stage IV pan-NET, grade 1 and 2, with no extra abdominal disease, 5-year survival was 64.7% (95% CI 48.2-81.2). As these survival rates exceed previously published series of LT for pan-NET, the evidence base for this treatment is very weak.

Long-term Outcomes of Lower Rectal Cancer Patients Treated with Total Mesorectal Excision and Lateral Pelvic Lymph Node Dissection after Preoperative Radiotherapy or Chemoradiotherapy

OBJECTIVES

The standard strategy for advanced rectal cancer (RC) is preoperative short-course radiotherapy (SCRT)/chemoradiotherapy (CRT) plus total mesorectal excision (TME) in Western countries; however, the survival benefit of adding chemotherapy to radiotherapy remains unclear. There is accumulating evidence that either SCRT/CRT or lateral pelvic lymph node dissection (LPND) alone may not be sufficient for local control of advanced RC. We herein retrospectively evaluated the clinical outcomes of patients who were treated by SCRT/CRT+TME+LPND, particularly focusing on the prognostic impact of lateral pelvic lymph node metastasis (LPNM).

METHODS

Patients diagnosed as having clinical Stage II and III lower RC who received SCRT/CRT+TME+LPND between 1999 and 2012 at our hospital were enrolled. Adverse events (AEs), surgery-related complications (SRC), and therapeutic effects were retrospectively analyzed.

RESULTS

Fifty cases (SCRT:25, CRT:25) were analyzed. No significant differences were observed in overall survival (OS), relapse-free survival (RFS), local recurrence (LR), AE, and SRC between the SCRT and CRT groups, although the pathological therapeutic effect was higher in the CRT group. The patients with LPNM showed significantly inferior 5-year OS and 5-year RFS than those without LPNM.

CONCLUSIONS

There were no significant differences in OS, RFS, or LR between SCRT and CRT, although CRT had a significantly greater histological therapeutic effect. The prognosis of the pathological LPNM-positive cases was significantly poorer than that of pathological LPNM-negative cases.

Pancreatic Duct Stricture That Rapidly Progressed to Pancreatic Ductal Adenocarcinoma and Formed a Mass within 3 Months: A Case Report

The natural growth rate of pancreatic carcinoma in situ with pancreatic duct stricture remains unclear. Herein, we present a case with pancreatic duct stricture that rapidly grew to form a mass lesion within 3 months. A 74-year-old woman was referred to us for the investigation of a pancreatic duct dilatation. Initial images did not reveal any clear mass lesions near the pancreatic duct stricture. Pancreatic juice cytology showed suspicious findings. Distal pancreatectomy was recommended; however, the patient refused to undergo surgical treatment at that time. Images taken 3 months later demonstrated a nodular pancreatic body mass which was identified as a moderately to poorly differentiated tubular adenocarcinoma. Previous reports have suggested that pancreatic carcinoma in situ and small pancreatic ductal adenocarcinoma require at least 1–2 years to progress to an advanced mass. This case suggests that pancreatic carcinoma in situ may grow rapidly and indicates a need for close follow-up in patients with pancreatic duct strictures, even if the pathological evidence is not confirmed.

The prognostic impact of para-aortic lymph node metastasis in pancreatic cancer: A systematic review and meta-analysis

PURPOSE

To evaluate by a meta-analytic approach the long-term prognostic impact of para-aortic lymph node (PALN) involvement in resected ductal adenocarcinoma of the pancreas.

METHODS

MEDLINE, Embase, PubMed and the Cochrane Library were searched from January 1990 to June 2015. Trials reporting Kaplan-Meier curves and comparing overall long-term survival of negative and metastatic PALN in patients who underwent resection for pancreatic cancer were included. Lymph nodes were classified according to the Japan Pancreatic Society rules and identified using hematoxylin and eosin staining. Hazard ratios (HRs) and 95%CI were estimated for each trial and pooled in a meta-analysis.

RESULTS

Thirteen eligible studies including 2141 patients (364 positive PALN; 1777 negative PALN) were identified. Most of the studies were retrospective. Heterogeneity among trials was high (I(2) = 98.7%; p < .001). PALN metastasis was associated with increased mortality when compared with patients with negative PALN regardless regional nodal status [HR 1.85, 95%CI 1.48-2.31; p < .001]. Median survival was significantly decreased in patients with positive PALN (WMD = -4.92 months 95%CI -6.40; -3.43; p < .001). Moreover, metastatic PALN affected mortality also when regional lymph nodes were positive [HR 1.67, 95%CI 1.34-2.08; p < .001]. No publication bias was detected.

CONCLUSIONS

PALN metastasis appears to correlate with poor prognosis in patients with pancreatic adenocarcinoma. The assessment of PALN status may be considered for a more accurate staging of the disease and appropriated subgroup survival reporting. However, the definitive avoidance of the resection in case of intraoperative metastatic PALN needs further investigation.

Proposing the lymphatic target volume for elective radiation therapy for pancreatic cancer: a pooled analysis of clinical evidence

BACKGROUND

Radiation therapy is an important cancer treatment modality in both adjuvant and definitive setting, however, the use of radiation therapy for elective treatment of regional lymph nodes is controversial for pancreatic cancer. No consensus on proper selection and delineation of subclinical lymph nodal areas in adjuvant or definitive radiation therapy has been suggested either conclusively or proposed for further investigation. This analysis aims to study the pattern of lymph node metastasis through a pooled analysis of published results after radical tumor and lymph nodal resection with histological study in pancreatic cancer.

METHODS

Literature search using electronic databases including MEDLINE, EMBASE, and CANCERLIT from January 1970 to June 2009 was performed, supplemented by review of references. Eighteen original researches and a total of 5954 pancreatic cancer patients underwent radical surgical resection were included in this analysis. The probability of metastasis in regional lymph nodal stations (using Japan Pancreas Society [JPS] Classification) was calculated and analyzed based on the location and other characteristics of the primary disease.

RESULTS

Commonly involved nodal regions in patients with pancreatic head tumor include lymph nodes around the common hepatic artery (Group 8, 9.79%), posterior pancreaticoduodenal lymph nodes (Group 13, 32.31%), lymph nodes around the superior mesenteric artery (Group 14, 15.85%), paraaortic lymph nodes (Group 16, 10.92%), and anterior pancreaticoduodenal lymph nodes (Group 17, 19.78%); The probability of metastasis in other lymph nodal regions were <9%.Commonly involved nodal regions in patients with pancreatic body/tail tumor include lymph nodes around the common hepatic artery (Group 8, 15.07%), lymph nodes around the celiac trunk (Group 9, 9.59%), lymph nodes along the splenic artery (Group 11, 35.62%), lymph nodes around the superior mesenteric artery (Group 14, 9.59%), paraaortic lymph nodes (Group 16, 16.44%), and inferior body lymph nodes (Group 18, 24.66%). The probability of metastasis in other lymph nodal regions were <9%.

CONCLUSIONS

Pancreatic cancer has a high propensity of regional lymphatic metastases; however, clear patterns including the site and probability of metastasis can be identified and used as a guide of treatment in patients with resectable pancreatic cancer. Further clinical investigation is needed to study the efficacy of elective treatment to CTV defined based on these patterns using high-dose conformal or intensity-modulated radiation therapy.

The number of lymph nodes identified in a simple pancreatoduodenectomy specimen: comparison of conventional vs orange-peeling approach in pathologic assessment

Lymph node status is one of the most important predictors of survival in resectable pancreatic ductal adenocarcinoma; therefore, thorough lymph node evaluation is a critical assessment in pancreatoduodenectomy specimens. There is considerable variability in pancreatoduodenectomy specimens processed histologically. This study compares two approaches of lymph node dissection and evaluation (standard vs orange peeling) of pancreatoduodenectomy specimens. A different approach to dissection of pancreatoduodenectomy specimens was designed to optimize lymph node harvesting: All peripancreatic soft tissues were removed in an orange-peeling manner before further dissection of the pancreatic head. This approach was applied to 52 consecutive pancreatoduodenectomy specimens performed for ductal adenocarcinoma at two institutions. Specimen dissection was otherwise performed routinely. Overall number of lymph nodes harvested, number of positive lymph nodes, and their anatomic distribution were analyzed and compared with cases that had been dissected by the conventional approach. The mean number of lymph nodes identified by the orange-peeling approach was 14.1 (by institution, 13.8 and 14.4), as opposed to 6.1 (by institution, 7 and 5.3) in cases processed by conventional approach (P=0.0001). The number of lymph node-positive cases also increased substantially from 50% (by institution, 54 and 46%) in the conventional method to 73% (by institution, 88 and 58%) in the orange-peeling method (P=0.02). The orange-peeling method of lymph node harvest in pancreatoduodenectomy specimens for ductal adenocarcinoma enhances overall and positive lymph node yield and optimizes ductal adenocarcinoma staging. Therefore, lymph node harvest by the orange-peeling method should be performed routinely before specimen sectioning in assessment of pancreatoduodenectomy for ductal adenocarcinoma.

Long-term survival after resection for ductal adenocarcinoma of the pancreas. Is it really improving?

OBJECTIVE

The authors review their recent experience with resected pancreatic ductal adenocarcinoma.

SUMMARY BACKGROUND DATA

Ductal adenocarcinoma of the pancreas has traditionally had a 5-year survival rate less than 10% after curative resection. Recently, several groups have reported markedly improved 5-year survival rates (approaching 25%) for patients undergoing curative resection.

METHODS

Institutional experience with 186 consecutive patients (1981-1991) with pathologic diagnoses of ductal adenocarcinoma undergoing pancreatic resection was reviewed. Histologic specimens of all 3-year survivors (n = 31) were re-reviewed by two pathologists, one internal and one external; nonductal pancreatic cancers then were excluded.

RESULTS

After histologic re-review, 12 patients did not have ductal adenocarcinoma, leaving a total of 174 patients for analysis (102 men, 72 women; mean age 63 years, range 34-82 years). Mean follow-up was 22 months (range 4-109). Classical pancreaticoduodenectomy was performed in 71%, pylorus-preserving resection in 9%, and total pancreatectomy in 20%. Hospital mortality was 3%. Twenty-eight patients (16%) had macroscopically incomplete resections; 98 (56%) had lymph node metastases within the resected specimens, and 21 patients (12%) had extensive perineural invasion. Overall actuarial 5-year survival was 6.8%. Five-year survival was greater for node-negative versus node-positive patients (14% vs. 1%, p < 0.001), and for smaller (< 2 cm) versus larger tumors (20% vs. 1%, p < 0.001). The 5-year survival for the subset of patients with negative nodes and no perineural or duodenal invasion (69 patients) was 23% (p < 0.001). Mean survival of the 12 excluded patients was 53 +/- 7 months compared with 17.5 +/- 1 months in the 174 patients with ductal pancreatic cancer.

CONCLUSIONS

Five-year survival for patients undergoing pancreatic resection for lesions deemed to be clinically "curable" intraoperatively and histologically reviewed/confirmed to be ductal adenocarcinoma of the pancreas is approximately 7%. Survival is greater (23%) in the subset of patients with negative nodes and no duodenal or perineural invasions. Pathologic review of all patients with pancreatic ductal cancer adenocarcinoma is mandatory if survival data are to be meaningful.

Three-dimensional studies on the structure of the tissue surrounding the superior mesenteric artery

The anatomy and topography of tissue surrounding the superior mesenteric artery were examined histopathologically, and the structure surrounding the superior mesenteric artery (SMA) was reconstructed with data from histologic examination and three-dimensional analyses. Specimens were obtained from three autopsy cases without abnormalities, two surgically resected cases of cancer of the pancreatic head, and one autopsy case of cancer of the pancreatic head. The endothelium or basal membrane of blood and lymph vessels were identified immunohistochemically, and the distribution of lymph nodes, blood vessels, lymph vessels, and collagen fibers was determined. The superior mesenteric plexus was found to be a relatively dense structure with a thickness of about 2 mm, composed of collagen fibers and connective tissue, which concentrically enveloped the small arteries, the superior mesenteric artery, nerve bundles, and capillaries. Lymph vessels larger than a few micrometers in diameter were often found outside of the plexus, and this plexus contained no lymph nodes in any sections. The three-dimensional study of the modes of spread along the superior mesenteric artery of pancreatic cancer revealed two types of spread: the tumor extends mainly by neural invasion, and the tumor extends mainly by lymph node metastases. These morphologic features suggest that lymphatic flow in the vicinity of the superior mesenteric artery passes primarily outside of the plexus, and complete excision of lymph nodes close to the superior mesenteric artery with preservation of the superior mesenteric plexus is feasible if there is no neural invasion into retropancreatic tissues.